First start with sverchok. looking for feedback and how can i make this more efficient
Let me just insert the gist
https://gist.github.com/b846e86e59d5458d0b87abba5205f6b2
This example of some ways to solve issue. I don't know aim of your node tree.
First of all, you can use not only extrude to extrude. loft, copy with uvconnect, matrix tubes, simple pipe node or whatever you need. There are tonns of solutions depend of what you want.
Import json and test.